Question

I am working in WordPress trying to use an ajax request to fetch user data by passing the user id.

I can see that the user id sends correctly via AJAX POST but I am getting an internal error message and I don’t know why.

At first I thought it was because I was trying to fetch some custom fields that I had added to the user profile but even when I simplified my script I am still getting the error message.

Any help is much appreciated!

Front End

$('.author').click(function() {

    var id   = $(this).attr('id');
    var temp = id.split('-');
    id = temp[1];

    $.ajax({
            type: 'POST',
            url: 'wp-content/themes/twentyeleven/author_info.php',
            data: {id: id},
            dataType: 'html',
            success: function(data) {
                $('#author-bio').html(data);        
            }
        });     

    return false;
});

author_info.php

$user_id = $_POST['id'];
$forename = get_the_author_meta('user_firstname', $user_id);
$output = $user_id;
echo $output;

Error Message

500 (Internal Server Error) jquery.min.js:4

Answer 1

Mathieu added a hackable approach to intercepting a request and redirecting it, which is fine. I prefer to build out AJAX responses that return json_encoded arrays.

$('.author').click(function() {

  var id   = $(this).attr('id');
  var temp = id.split('-');
  id = temp[1];

  $.ajax({
    url: 'http://absolute.path/wp-admin/admin-ajax.php',
    data: {'action' : 'ajax_request', 'fn': 'getAuthorMeta', 'id': id},
    dataType: 'json',
    success: function(data) {
      //We expect a JSON encoded array here, not an HTML template.       
    }
  });     
  return false;
});

Now we build out the function to handle our ajax requests.

First, we need to define our ajax add_action method ->

add_action('wp_ajax_nopriv_ajax_request', 'ajax_handle_request');
add_action('wp_ajax_ajax_request', 'ajax_handle_request');

We need to use both add_action lines here. I won’t get into why. You’ll notice the _ajax_request here. This is the ‘action’ that we sent over in our AJAX function data: {'action' : 'ajax_request'}. We use this hook to validate our AJAX request, it can be anything you’d like.

Next, we’ll need to build out or function ajax_handle_request.

function ajax_handle_request(){
  switch($_REQUEST['fn']){
    case 'getAuthorMeta':
      $output = ajax_get_author_meta($_REQUEST['id']);
      break;
    default:
      $output = 'That is not a valid FN parameter. Please check your string and try again';
      break;
  }
  $output = json_encode($output);
  if(is_array($output)){
    return $output;
  }else{
    echo $output;
  }
}

Now let’s build our function to actually get the author meta.

function ajax_get_author_meta($id){
  $theMeta = get_the_author_meta([meta_option], $id);
  return $theMeta;
}

Where [meta_option] is a field provided by WP’s native get_the_author_meta function.

At this point, we’ll now go back to our success:function(data) and (data) is a reference to the json_encoded array we’ve returned. We can now iterate over the object to get our fields and output them into the page as you’d like.